Very volatile situation in Ukraine will president -- and move in with military might. Despite those warnings against it from the White House tonight we've just learned of a phone call between President Putin and President Obama right there in the Oval Office. That call comes just hours after President Obama warned there would be a cost if Russia makes any military move. We have two reports here tonight Jon Karl standing by the White House the first ABC's -- -- court in Ukraine. What many are asking about the men in uniform gathering already Alex. Good evening David the Russian military has already been seen moving around here as mysterious unidentified pro Russia militia groups continue seizing government buildings and airports and tonight the unrest is spreading. In one city today. Pro Russia demonstrators furiously beat supporters of the new Ukrainian government forcing them to -- children to their -- -- bloody. Okay. -- this part of eastern Ukraine flags on government buildings torn down and replaced with Russia's. From Crimea -- -- eastern cities along Russia's border Russian fervor is growing. Their efforts -- -- -- unanimous parliament vote tonight and authorizing military force in Ukraine. There is no mistaking the mood here in Crimea where most see themselves not as -- -- What -- Russians and many here would welcome the Russian army -- open arms. And he's the one people. -- rules process Ukrainian -- one people you want the Russian army to come here -- some -- both women it's not a Russian. Equipment and -- -- us. -- -- -- grows more and more divided President Obama has warned Russia against military action. It costs for any military intervention in Ukraine. That American warning clearly falling on deaf ears in Moscow. Tonight Ukraine's acting president called for calm but said the military is at its highest alert level. David -- -- court tonight Alex thank you wanted to get our chief White House correspondent John Karl also working this breaking story on a Saturday night John. We've heard the president there for 24 hours ago warning food and now we -- of this phone calls we know anything about what was said. White House officials tell me David that the president directly called on prudent to -- Russian forces back to their bases. And according to the White House the language used in this call was extraordinarily tough. The president called Russia's action quote. A clear violation and breach of international law in terms of what he would do about it in the call the president raised the possibility that the US would. Would cancel participation in upcoming meetings with Russia. Including possibly that -- summit in Sochi in June but -- last -- -- -- reported military options were off the table does that remain the case tonight. Absolutely there is no discussion here of any US military involvement in this crisis what --

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